.\" $Id: l2tpd.8,v 1.1.48.1 2005/08/08 12:05:25 honor Exp $ 
.\" LIC: GPL
.TH L2TPD 8 "11 March 2002"
.UC 4
.SH NAME
l2tpd \- user-space L2TP daemon.
.SH SYNOPSIS
.B l2tpd \fR[\fIoptions\fR]

.SH DESCRIPTION
\fBl2tpd\fR is a user-space L2TP daemon.  L2TP is the Layer Two
Tunneling Protocol described in RFC 2661.  It allows you to tunnel
PPP sessions over a network or transport protocol (in this case, UDP.)

.SH OPTIONS
.TP
.B \-d \fInum\fR
Sets the debug level to \fInum\fR.  Of interest mostly to
\fBl2tpd\fR developers.  \fInum\fR is a bitmask; set it to
65535 for maximum debugging information.

.TP
.B \-f
Do not fork.  Normally, \fBl2tpd\fR forks and puts itself in the
background.  This option causes it to stay running in the foreground.

.SH L2TPD ARCHITECTURE

The \fBl2tpd\fR program itself contains \fIonly\fR code necessary
for processing L2TP datagrams and maintaining L2TP tunnels and
sessions.  It does \fInot\fR contain code for interacting with
\fBpppd\fR or for users to control session establishment and teardown.
These functions are performed by \fIhandlers\fR, which are
shared-object libraries dynamically loaded at run-time.
.PP
The handlers currently distributed with \fBl2tpd\fR include:
.TP
.B sync-pppd.so
A shared-library which interfaces with \fBpppd\fR and allows \fBl2tpd\fR
to act as both an LAC and an LNS.
.TP
.B cmd.so
A simple command-interpreter which listens on a UNIX-domain socket
and allows you to start and stop L2TP sessions.
.PP
\fBl2tpd\fR is a single-threaded, event-driven program.  It should be
fairly lightweight and efficient.

.SH L2TPD CONFIGURATION
On startup, \fBl2tpd\fR reads the configuration file \fB/etc/l2tp/l2tp.conf\fR.
This configuration file sets operating parameters, describes peers and loads
and configures handlers.  See \fBl2tp.conf\fR(5) for configuration
file details.

.SH FILES
.TP
.B /etc/l2tp/l2tp.conf
Main configuration file.
.TP
.B /var/run/l2tpctrl
Control socket for \fBcmd.so\fR handler.

.SH AUTHORS
\fBl2tpd\fR was written by David F. Skoll <dfs@roaringpenguin.com>.

